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1.
According to modal interpretations of quantum mechanics, an observable Q can possess a definite value even when the quantum state is not an eigenstate of Q. In this paper, I discuss some interpretive difficulties faced by modal theorists. First, expanding upon Albert and Loewer, I identify two reasons why real-life measurements are never ideal, and I discuss why these considerations bode ill for modal interpretations. Second, I show that modal interpretations provide a less satisfactory explanation of interference effects than is provided by pilot-wave interpretations.  相似文献   

2.
The dependence of the magnetostriction constant of different materials in the form of a wire on the elastic elongation was measured. With pure nickel the magnetostriction constant is independent of the elastic deformation. All three alloys of iron and nickel and the triple alloy Fe-Ni-Co exhibit a linear dependence on the deformation, which differs for different crystallographic texture. In two iron-nickel alloys the dependence of the magnetostriction constants of the single crystal on the elastic deformation was calculated from measurements on polycrystals having different crystallographic textures. In the triple alloy Fe-Ni -Co a considerable linear decrease in the volume magnetostriction with the elastic elongation was also found. The observed changes can be explained by assuming the influence of the lattice deformation on the spinorbital interaction in alloys.
-
. . - Fe-Ni-Co , . - . , Fe-Ni-Co . - .


A preliminary report on some of the results of this paper was given at the conference on magnetism in Kyoto (Japan) in September 1961.

In conclusion the authors thank Z. Frait C. Sc. and S. Libovický for remarks, J. Míová for help in the measurements, members of the chemical department of our institute for annealing and analyzing the samples and members of the Metal Research Institute in Panenské Beany for their exceptional helpfulness in preparing the wires.  相似文献   

3.
    
. + + , , ; , , , . . , . . , . . .  相似文献   

4.
The magnetostriction constant of nickel was measured as a function of plastic deformation up to an elongation of 30%. The values of the magnetostriction constant in deformed samples deviate considerably, a fact which cannot be explained by errors of measurement. The absolute value of the magnetostriction constant decreases with increasing plastic deformation (by around 5%).
30% . , . ( 5%).


In conclusion the authors thank J. Kaczér, C. Sc. and B. esták, C. Sc. for carefully reading the paper and for their remarks, J. Míová for help in the measurements and workers of the chemical department of our Institute for careful preparation of the samples.  相似文献   

5.
6.
Particle creation by a black hole is described in terms of temperature corrections to the Casimir effect. The results of Levin, Polevoy, and Ritov for spectral and total Poynting vector for a fluctuating electromagnetic field in a plane vacuum gap between two arbitrary media with different temperatures in flat spacetime are applied to clarify the situation that exists between the horizon of a nonrotating black hole and spatial infinity. This helps to reveal the mechanism of particle creation. The Hawking radiation is born inside the bell formed by a potential barrier of a black hole in all the region [2M, ]. Its blackbody spectrum is due to the interaction of field fluctuations with the surface of the bell. The particles between the walls are virtual ones. They can become real after passing through the [3M, ] tail, appearing to an observer at future infinityJ + as real ones. The arguments for and against the present standpoint are discussed.  相似文献   

7.
8.
The paper discusses the absorption of the energy of a high-frequency field by a magnetic sample from the point of view of the interaction of spin waves with photons and spin waves amongst themselves. A general expression for the form of the absorption curve is derived, using the method known from the quantum theory of radiation and assuming very weak fields.
. , , .


The author thanks S. Krupika, Candidate of Sciences, for the exceptional interest taken in this work, for advice and a number of helpful and critical remarks.  相似文献   

9.
The Dirac spinors and matrices are used in combination with the Arnowitt-Deser-Misner formalism in order to obtain yet another formulation of Hamiltonian general relativity, together with a new form of the Gauss-Codazzi equations. The relation with Ashtekar's variables is analyzed; it is shown, for instance, that the matrices are equivalent to the electric field variable. The electric and magnetic decomposition of the gravitational field is also studie using Dirac matrices.  相似文献   

10.
In connection with another article by the author, we show how it might be possible to travel faster than the speed of light. We show that for clocks and rods moving faster than the speed of light, we get instead of time dilation and Lorentz contraction, respectively, time contraction and Lorentz expansion, respectively. It is shown that this paper is in confirmation with earlier articles dealing with this subject.  相似文献   

11.
The crucial problem of physics was first formulated by Democritus in the 5th century BC: to find the or smallest uncuttable bits of matter. That has not changed ever since. Among the current candidates are electron and positron, the least expensive of today's bona fide . Experimental tests of their non-compositeness by precisely measuring the gyromagnetic ratios of the individual trapped particles are reviewed.You know, it would be sufficient to really understand the electron.Albert Einstein  相似文献   

12.
13.
In a systematic study of the transfer process to sulphur dioxide, in seven different H2 + SO2 gas mixtures, the time spectra of the muonic sulphur X-rays yield muon transfer rates to the SO2 molecule, deduced from the lifetimes of the p atoms, which agree all well with each other. The muonic oxygen time spectra show an additional structure as if p atoms of another kind were present. Reduced transfer ratesO are reproducible if one uses the model of ephemeral p atoms. The intensity ratios between the different kinds of p atoms are also discussed in the framework of this model and the one of black and white p atoms.  相似文献   

14.
It is shown how to construct infinitely many conserved quantities for the classical non-linear Schrödinger equation associated with an arbitrary Hermitian symmetric spaceG/K. These quantities are non-local in general, but include a series of local quantities as a special case. Their Poisson bracket algebra is studied, and is found to be a realization of the half Kac-Moody algebrak R [], consisting of polynomials in positive powers of a complex parameter which have coefficients in the compact real form ofk (the Lie algebra ofK).  相似文献   

15.
I consider various experiments related to the so-called macroscopic quantum coherence experiment, which are probably at present in the class of thought experiment but are likely to become realistic in the next few decades. I explore the way in which outcomes consistent with the predictions of quantum mechanics would be interpreted by an adherent of, respectively, the Copenhagen, statistical, and Bohmian interpretations of the formalism.  相似文献   

16.
The problem of conduction modulation of laser radiation is considered. It is shown that acoustic wave interacting with photon field in active medium causes a periodic modulation of the number of quanta in the single-mode gas laser. The problem of modulation is solved quantum mechanically and it is shown that dielectric and conduction modulation give similar results.  相似文献   

17.
We present and discuss the derivation of a nonlinear nonlocal integrodifferential equation for the macroscopic time evolution of the conserved order parameter (r, t) of a binary alloy undergoing phase segregation. Our model is ad-dimensional lattice gas evolving via Kawasaki exchange with respect to the Gibbs measure for a Hamiltonian which includes both short-range (local) and long-range (nonlocal) interactions. The nonlocal part is given by a pair potential dJ(|x–y|), >0 x and y in d, in the limit 0. The macroscopic evolution is observed on the spatial scale –1 and time scale –2, i.e., the density (r, t) is the empirical average of the occupation numbers over a small macroscopic volume element centered atr=x. A rigorous derivation is presented in the case in which there is no local interaction. In a subsequent paper (Part II) we discuss the phase segregation phenomena in the model. In particular we argue that the phase boundary evolutions, arising as sharp interface limits of the family of equations derived in this paper, are the same as the ones obtained from the corresponding limits for the Cahn-Hilliard equation.  相似文献   

18.
    
, B. A. .  相似文献   

19.
Localised configurations of the free electromagnetic field are constructed, possessing properties of massive, spinning, relativistic particles. In an inertial frame, each configuration travels in a straight line at constant speed, less than the speed of lightc, while slowly spreading. It eventually decays into pulses of radiation travelling at speedc. Each configuration has a definite rest mass and internal angular momentum, or spin. Each can be of electric or magnetic type, according as the radial component of the magnetic or electric field vanishes in the rest frame, and each has an antiparticle. Any such configuration, of electric or magnetic type, is characterized in part by a set of labels (, 0, ,l, m), where 0 is the mean of the angular frequencies of the plane waves making up the configuration, is the variance of those frequencies, is a positive constant with dimensions of action, andl, m are angular momentum quantum numbers withl a positive integer andm an integer such that ml. The rest energy of the particle is 0, its spin is m, and its lifetime is of the order of 1/. Its antiparticle has 0 replaced by –0.  相似文献   

20.
Critical temperature of the classical O(N) spin model in two dimensions is investigated. We show that no phase transition exists in the system if the inverse temperature is less than c=c(N), where c(N) is a constant such that c(N) > const. N log N.  相似文献   

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